When Manny Pacquiao voiced his opposition to gay marriage last week in an interview with examiner.com, he set off a firestorm that got him briefly banned from the place all Americans deem holy: the mall.

Rick Caruso, the owner of The Grove, a Los Angeles outdoor mall, tweeted that “Boxer Manny Pacquiao is not welcome at @TheGroveLA.” He explained that “@TheGroveLA is a gathering place for all Angelenos, not a place for intolerance.”

Caruso eventually removed the ban, pleading confusion over whether Pacquiao had called for violence against gay people (he hadn’t), and so the boxer was spared the humiliation of having to do his Crate&Barrel and Gap shopping online.

But why are businesses pushing their political opinions in our faces, anyway?

Here in New York, Manhattan Mini-Storage has been inflicting lame anti-Republican ads on us for several years. Philadelphians hoping for some of the city’s best cheesesteaks at Geno’s must contend with signs illustrating the late owner’s support for “English-only” and the National Rifle Association. The soap company Lush is openly involved in Palestinian causes.

What does politics have to do with storage, cheesesteaks or soap?

The Pacquiao/Grove controversy, however, sets a precedent: A business actually banned someone for having the “wrong” political opinion.

By citing Pacquiao’s supposed “intolerance” — i.e., opposing gay marriage — the mall also made unwelcome anyone who agrees with Pacquiao on gay marriage. This, in a state in which more than 7 million people voted for Proposition 8, a ballot initiative that amended the state Constitution to prohibit gay marriage. That’s bold.

It used to be that some people would send a political message with the businesses they chose to support or shun. But for a business to say it doesn’t want the money of those with whom it disagrees is a different matter entirely.

During George W. Bush’s presidency, when no celebrity could withhold his or her political outbursts, “Shut up, and sing” became the rally call for exasperated conservatives sick of hearing lectures at concerts. It doesn’t seem that “Shut up, and let me shop” will have quite the same ring to it.

It will be interesting to see if any other businesses follow The Grove’s lead and let shoppers know they’re unwelcome if their politics aren’t preapproved. In this economy, it seems more than a little unwise.